Project Summary The ability to instantiate and maintain goal representations in short-term (?working?) memory (WM) is central to human capacities for flexible thought and goal-directed behavior. Critically, human aging is associated with a decline in the ability to control what gains access to and is maintained in WM (?executive? hypothesis of aging). While the executive hypothesis has been well-studied in recent years in context of neurocognitive aging, it remains poorly understood whether these changes are consequential to goal-directed behavior in daily life. As a novel approach to this issue, in the present set of studies we will examine the contribution of brain imaging, lab-based, and momentary (i.e. daily/within-day) assessments of WM to self-regulation of health promotion behavior (specifically, physical activity). Recent evidence shows that individual differences in executive control are a primary determinant of an individual?s ability to successfully translate physical activity goals into daily behavior (i.e. self-regulatory capacity). However, this has been understudied in middle-aged and older adults in whom the efficiency of WM and affiliated brain networks are subject to alteration. An important next step is to examine WM and self-regulation at the level of behavior in naturalistic settings. The NIH/NIA K99/R00 Pathway to Independence Award is being sought to provide the PI training in ambulatory measurement methodology (ecological momentary assessments, EMA) and the resources to conduct a novel longitudinal study of younger, middle-aged, and older adults focused on the role of momentary WM abilities in self-regulation of physical activity. The use of smart phone-based EMA will provide a glimpse into the daily lives of study participants, providing a novel opportunity to examine how neurocognitive resources and lab- based assessments of control over WM project out to intra-individual trajectories of cognition and behavior. The current proposal will: 1) Examine the contribution of WM to self-regulation of health promotion behavior and health/well- being outcomes in middle-aged and older adults. Individuals who self-report high self-regulation achieve generally superior health and well-being outcomes. However, the role control over WM processing plays in moderating these achievements has been understudied. 2) Develop novel ambulatory measures of WM capacity. Lab-based executive control tasks are less suitable for ambulatory deployment. EMA of WM capacity will place objective assessment of controlled cognition in close proximity of real-time self-regulation of behavior. 3) Examine how individual differences in the neurocognitive resources that underlie WM processing project out into intra-individual trajectories of health promotion behavior. We expect that age-related declines/maintenance of the neurocognitive resources that support WM processing will play a key role in determining an individual?s capacity to self-regulate physical activity.